Conventionally, car navigation devices equipped with map storage means, input means, search means and present position calculation means have been known. The devices are to show guide information such as the course or traveling direction of the next intersection at just the right time in relation to a present position.
Navigation methods for transmitting a route result searched at a center have also known in the conventional, for example, as proposed and disclosed in Japanese unexamined patent publication Nos. 2000-46567, Hei 11-296074, 2000-113388, 2000-123295 and 2000-155896, which can reduce the amount of data to be transmitted from the center to a terminal, and communication time and costs.
With route guidance information generating devices and methods, a method and device for automatically forming a deformation map as disclosed in Japanese unexamined patent publication No. Hei 10-198267, and a navigation device and method as disclosed in Japanese unexamined patent publication No. 2000-155035 are known. A technique for representing an overview of a guide route as a deformation map or patterned text stored on a provided medium is also known.
In the above-mentioned prior art, however, a hardware configuration of a terminal is such that a display screen is small, and underperforming CPU and memory can only perform simple control processing, or response time during which a user has to wait until route guidance information desired by the user is displayed and the point as to whether expression is possible on the small display screen are not considered, which results in problems that the conventional technology makes the response time long and operability bad, and can not display or determine the route on such a terminal only with a small display screen. Further, since the above-mentioned conventional communication-type navigation system is premised on use of a relatively big display screen and a navigation-only terminal with relatively large memory capacity, it also has such a problem that the system becomes expensive.